Optical pickup device

ABSTRACT

In an optical pickup device, a first and a second short-cutting terminal  40  and  50  are interposed in parallel between terminals of a laser diode  1 . The first short-cut terminal  40  is disposed on a side surface of a housing. The second short-cut terminal  50  is disposed on a rear surface of the housing.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an optical pickup device.

[0003] 2. Description of the Related Art

[0004] In an optical pickup device in which a laser diode is mounted in a housing, a shortcut terminal for soldering is interposed between the terminals of the laser diode so as to prevent the electrostatic breakdown of the laser diode. FIG. 4 shows a circuit diagram of a laser diode 1 and a short-cut terminal 2 which are adopted in a conventional optical pickup device.

[0005] In the conventional optical pickup device having the circuit shown in FIG. 4, the electrostatic breakdown of the laser diode 1 is prevented by soldering the short-cut terminal 2 in advance for shortcircuiting.

[0006] With respect to the optical pickup device, not only is it necessary to keep the electrostatic breakdown of the laser diode prevented in its manufacturing line, but it is also necessary to keep the electrostatic breakdown of the laser diode prevented in the processing of mounting the optical pickup device in an apparatus to which the optical pickup device is set. For this purpose, when the laser diode is in an ungrounded state, the aforementioned short-cut terminal is conventionally shortcircuited by soldering both during the passage of the manufacturing line and after its mounting in the setting apparatus.

[0007] In addition, JP-A-5-335689 discloses an optical pickup device in which the terminals of a semiconductor laser are connected in advance in a shortcircuited state, and the shortcircuiting connection is broken when a voltage is applied to the semiconductor laser.

[0008] However, in the case where the short-cut terminal 2 shown in FIG. 4 is disposed on the side surface of the housing of the optical pickup device, although the operation of soldering and shortcircuiting the short-cut terminal 2 can be effected easily in the manufacturing line where the optical pickup devices are handled as single pieces, after the mounting of the optical pickup device in the setting apparatus, there has been a problem in that the other component parts on the setting apparatus side get in the way, and it is not easy to bring a soldering iron close to the short-cut terminal 2 disposed on the side surface of the housing, causing a decline in the operational efficiency at the time of soldering.

[0009] To cope with this problem, it is conceivable to dispose the short-cut terminal 2 on the rear surface of the housing of the optical pickup device. In this case, it is easy to solder and shortcircuit the short-cut terminal 2 after mounting the optical pickup device in the setting apparatus; however, in the manufacturing line where the optical pickup devices are handled as single pieces, there has arisen such a problem that, when the housing is reversed and the short-cut terminal on the rear surface is soldered, a lens unit attached by being merely inserted in a column on an obverse surface side of the housing becomes possibly dislocated from the column and comes off.

[0010] Furthermore, since only one short-cut terminal is conventionally provided, there has been a problem in that if the short-cut terminal burns, the optical pickup unit itself becomes unusable.

SUMMARY OF THE INVENTION

[0011] The invention has been devised in view of the above-described problems, and its object is to provide an optical pickup device which is capable of overcoming the problem concerning the burning of the short-cut terminal, the problem concerning the operational efficiency at the time of soldering, and the problem concerning the coming off of the laser unit.

[0012] To achieve the above object, according to the invention, there is provided an optical pickup device in which a short-cutting terminal is interposed between terminals of a laser diode mounted in a housing, characterized in that a first and a second short-cutting terminal are interposed in parallel between the terminals of the laser diode.

[0013] According to this optical pickup device, in case where one short-cut terminal has burned, the electrostatic breakdown of the laser diode can be prevented by shortcircuiting the other short-cut terminal by solder. In addition, of the two short-cut terminals, it is possible to effect soldering by selecting one which can be easily soldered, and effect soldering by selecting one which can be soldered without reversing the housing. Therefore, it becomes possible to readily perform the soldering operation of the short-cut terminals in the manufacturing line and in the stage after the mounting of the optical pickup device in the setting apparatus.

[0014] In this invention, it is preferred that the first short-cut terminal and the second short-cut terminal be respectively disposed on two different surfaces of the housing. In addition, it is preferred that the first short-cut terminal be disposed on a side surface of the housing, and that the second short-cut terminal be disposed on a rear surface of the housing. Through these arrangements as well, the above-described advantages ca be offered.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIG. 1 is a side elevational view of an optical pickup device in accordance with an embodiment of the invention;

[0016]FIG. 2 is a view taken in the direction of arrow II in FIG. 1;

[0017]FIG. 3 is a circuit diagram of a laser diode and two short-cut terminals which are adopted in the optical pickup device in accordance with the embodiment;

[0018]FIG. 4 is a circuit diagram of a laser diode and a short-cut terminal which are adopted in a conventional optical pickup device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Now, a description will be given in more detail of an embodiment of the invention with reference to the accompanying drawings.

[0020]FIG. 1 is a side elevational view of an optical pickup device, and FIG. 2 is a view taken in the direction of arrow II in FIG. 1. In these drawings, reference numeral 10 denotes a housing; 20, a shield cover surrounding a photodiode mounted in the housing 10; and 30, a flexible wiring board. In this optical pickup device, a first short-cut terminal 40 for soldering is disposed on a side surface 12 of the housing 10 as shown in FIG. 1, while a second short-cut terminal 50 for soldering is disposed on a rear surface 13 of the housing 10 as shown in FIG. 2.

[0021]FIG. 3 shows a circuit diagram of a laser diode 1 and the first and second two short-cut terminals 40 and 50 which are adopted in the optical pickup device in accordance with this embodiment. As shown in the drawing, the first and second two short-cut terminals 40 and 50 are interposed in parallel between the terminals of the laser diode 1. In the optical pickup device having the circuit shown in FIG. 3, the electrostatic breakdown of the laser diode 1 is prevented by soldering and shortcircuiting in advance one of the first and second short-cut terminals 40 and 50.

[0022] Accordingly, in case where the first short-cut terminal 40 has burned, the electrostatic breakdown of the laser diode 1 can be prevented by soldering and shortcircuiting the second short-cut terminal 50. On the other hand, in case where the second short-cut terminal 50 has burned, the electrostatic breakdown of the laser diode 1 can be prevented by soldering and shortcircuiting the first short-cut terminal 40.

[0023] In addition, in a manufacturing line where the optical pickup devices are handled as single pieces, the electrostatic breakdown of the laser diode is prevented by soldering and shortcircuiting the first short-cut terminal 40 which is disposed on the side surface 12 of the housing 10 and which can be easily soldered. After the optical pickup device is mounted in a setting apparatus, the electrostatic breakdown of the laser diode can be prevented by soldering and shortcircuiting the second short-cut terminal 50 disposed on the rear surface 13 of the housing 10 where the soldering work is not hampered by other component parts on the setting apparatus side. It should be noted that after the optical pickup device is mounted in the setting apparatus, since a cover and the like on the setting apparatus side are disposed on the lens unit described at the beginning, even if the housing 10 is reversed together with the setting apparatus, a situation does not occur in which the lens unit becomes dislocated and comes off the column described at the beginning.

[0024] It should be noted that in the manufacturing line of the optical pickup device and in the stage after the incorporation of the optical pickup device into the setting apparatus, when the laser diode 1 is grounded, since it is unnecessary to keep both first and second short-cut terminals 40 and 50 shortcircuited, the solder is removed at that time to keep the laser diode 1 in an insulated state.

[0025] As described above, in accordance with this invention, with the optical pickup device it is possible to overcome the problem concerning the burning of the short-cut terminal, the problem concerning the operational efficiency at the time of soldering, and the problem concerning the coming off of the laser unit which have been described at the beginning. 

What is claimed is:
 1. An optical pickup device, comprising: a housing; a laser diode having terminals and mounted in said housing; first and second short-cutting terminals interposed in parallel between the terminals of said laser diode.
 2. The optical pickup device according to claim 1 , wherein said first short-cut terminal and said second short-cut terminal are disposed on two different surfaces of said housing, respectively.
 3. The optical pickup device according to claim 2 , wherein said first short-cut terminal is disposed on a side surface of said housing, and said second short-cut terminal is disposed on a rear surface of said housing. 